In the Linux kernel, the following vulnerability has been resolved:
HID: appletb-kbd: fix UAF in inactivity-timer cleanup path
Commit 38224c472a03 ("HID: appletb-kbd: fix slab use-after-free bug in
appletb_kbd_probe") added timer_delete_sync(&kbd->inactivity_timer) to
both the probe close_hw error path and appletb_kbd_remove(), but the
way it was wired in left the inactivity timer reachable during driver
tear-down via two distinct windows.
Window A -- put_device() before timer_delete_sync():
put_device(&kbd->backlight_dev->dev);
timer_delete_sync(&kbd->inactivity_timer);
The inactivity_timer softirq reads kbd->backlight_dev and calls
backlight_device_set_brightness() -> mutex_lock(&ops_lock). If a
concurrent hid_appletb_bl unbind drops the last devm reference
between these two calls, the backlight_device is freed and the
mutex_lock() touches freed memory.
Window B -- backlight cleanup before hid_hw_stop():
if (kbd->backlight_dev) {
timer_delete_sync(...);
put_device(...);
}
hid_hw_close(hdev);
hid_hw_stop(hdev);
Even after Window A is closed, hid_hw_close()/hid_hw_stop() still run
afterwards, so a late ".event" callback from the HID core (USB URB
completion on real Apple hardware) can arrive after
timer_delete_sync() drained the softirq but before put_device() drops
the reference. That callback reaches reset_inactivity_timer(), which
calls mod_timer() and re-arms the timer. The freshly re-armed timer
can then fire on the about-to-be-freed backlight_device.
Both windows produce the same KASAN slab-use-after-free:
BUG: KASAN: slab-use-after-free in __mutex_lock+0x1aab/0x21c0
Read of size 8 at addr ffff88803ee9a108 by task swapper/0/0
Call Trace:
<IRQ>
__mutex_lock
backlight_device_set_brightness
appletb_inactivity_timer
call_timer_fn
run_timer_softirq
handle_softirqs
Allocated by task N:
devm_backlight_device_register
appletb_bl_probe
Freed by task M:
(concurrent hid_appletb_bl unbind path)
Close both windows at once by reworking the tear-down in
appletb_kbd_remove() and in the probe close_hw error path so that
1) hid_hw_close()/hid_hw_stop() run before the backlight cleanup,
guaranteeing no further .event callback can fire and re-arm the
timer, and
2) inside the "if (kbd->backlight_dev)" block, timer_delete_sync()
runs before put_device(), so the softirq is drained before the
final reference is dropped.
References
Configurations
Configuration 1 (hide)
|
History
10 Jun 2026, 19:16
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Linux linux Kernel
Linux |
|
| CWE | CWE-416 | |
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.16:-:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.16:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.16:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.8 |
| References | () https://git.kernel.org/stable/c/4db2af929279c799b5653a39eb0795c72baffca4 - Patch | |
| References | () https://git.kernel.org/stable/c/59a79938ca5541fe55d675304116b7ea684afef0 - Patch | |
| References | () https://git.kernel.org/stable/c/93d989e47bc316c793a69c6a332e053c90e29f02 - Patch |
28 May 2026, 10:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-05-28 10:16
Updated : 2026-06-10 19:16
NVD link : CVE-2026-46213
Mitre link : CVE-2026-46213
CVE.ORG link : CVE-2026-46213
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
Use After Free